Revert 251207 "Use gpu::Mailbox instead of std:string in IPCs"

trunk/src/content/common/gpu/texture_image_transport_surface.cc

Index: trunk/src/content/common/gpu/texture_image_transport_surface.cc
===================================================================
--- trunk/src/content/common/gpu/texture_image_transport_surface.cc	(revision 251280)
+++ trunk/src/content/common/gpu/texture_image_transport_surface.cc	(working copy)
@@ -218,7 +218,9 @@
   GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params params;
   params.size = backbuffer_size();
   params.scale_factor = scale_factor_;
-  params.mailbox = back_mailbox_;
+  params.mailbox_name.assign(
+      reinterpret_cast<const char*>(&back_mailbox_),
+      sizeof(back_mailbox_));
 
   glFlush();
 
@@ -256,7 +258,9 @@
   params.y = y;
   params.width = width;
   params.height = height;
-  params.mailbox = back_mailbox_;
+  params.mailbox_name.assign(
+      reinterpret_cast<const char*>(&back_mailbox_),
+      sizeof(back_mailbox_));
 
   glFlush();
 
@@ -290,17 +294,18 @@
 void TextureImageTransportSurface::OnBufferPresented(
     const AcceleratedSurfaceMsg_BufferPresented_Params& params) {
   if (params.sync_point == 0) {
-    BufferPresentedImpl(params.mailbox);
+    BufferPresentedImpl(params.mailbox_name);
   } else {
     helper_->manager()->sync_point_manager()->AddSyncPointCallback(
         params.sync_point,
         base::Bind(&TextureImageTransportSurface::BufferPresentedImpl,
                    this,
-                   params.mailbox));
+                   params.mailbox_name));
   }
 }
 
-void TextureImageTransportSurface::BufferPresentedImpl(const Mailbox& mailbox) {
+void TextureImageTransportSurface::BufferPresentedImpl(
+    const std::string& mailbox_name) {
   DCHECK(is_swap_buffers_pending_);
   is_swap_buffers_pending_ = false;
 
@@ -316,8 +321,11 @@
   DCHECK(backbuffer_.get());
 
   bool swap = true;
-  if (!mailbox.IsZero()) {
-    if (mailbox != back_mailbox_) {
+  if (!mailbox_name.empty()) {
+    DCHECK(mailbox_name.length() == GL_MAILBOX_SIZE_CHROMIUM);
+    if (!memcmp(mailbox_name.data(),
+                &back_mailbox_,
+                mailbox_name.length())) {
       // The browser has skipped the frame to unblock the GPU process, waiting
       // for one of the right size, and returned the back buffer, so don't swap.
       swap = false;